High-resolution Insights into Africa's Escalating Flood Risks and Socio-economic Vulnerability

Many low- and middle-income countries in Africa face heightened flood risks and significant socio-economic impacts due to climate change, despite contributing minimally to global emissions. However, current flood datasets often lack the necessary resolution (above 250m) and duration to focus effectively on floods in these regions, complicating climate mitigation and adaptation efforts. This study aims to develop long-term, high-resolution spatiotemporal datasets to better characterize flood patterns and their socio-economic impacts across Africa. Using satellite imagery from Landsat and Sentinel-2, we mapped monthly flood inundation extents from 1984 to 2024, producing a flood dataset with a high spatial resolution of 30m to 10m for the entire African continent. We integrated these flood data with socio-economic metrics—population, GDP, and displacement figures—to assess socio-economic vulnerability across African countries. The results show that most African countries have witnessed an increase in affected population by floods over the past 40 years, with Comoros rising by 11.5% of the total population, Madagascar by 6.9%, Liberia by 5.7%, and Congo by 4.3%, identifying these countries as hotspots. In the last decade alone, flood-induced displacements have affected nearly 15 million people, predominantly in low-income countries, while upper-middle-income countries have shown better resilience in flood response. With the growing prevalence of floods and their uneven socio-economic repercussions, these high-resolution datasets are indispensable for shaping effective climate adaptation and mitigation measures, enabling precise and targeted actions. Policies should focus on strengthening flood response capacities and prioritizing support for socio-economically vulnerable regions to minimize flood-related consequences.